1. Field of the Invention
This invention relates to a floor panel.
More particularly, it relates to a floor panel comprising coupling parts at least at two opposite sides, in the form of a male coupling part and a female coupling part, respectively, which allow to connect two of such floor panels to each other at the aforementioned sides by providing one of these floor panels with the pertaining male coupling part, by means of a downward movement, in the female coupling part of the other floor panel, such that thereby at least a locking in horizontal direction is obtained.
2. Related Art
Couplings allowing to couple two floor panels to each other by joining one floor panel with a downward movement into the other, in practice are subdivided into two kinds, namely a first kind wherein the coupling parts exclusively provide for a horizontal locking, without any presence of a locking in vertical direction, and a second kind wherein a horizontal as well as a vertical locking are provided for.
The couplings of the first kind are also known as so-called “drop-in” systems. Floor panels equipped with those at two opposite sides are known, amongst others, from CA 991.373 and JP 07-300979. As is evident from these patent documents, such “drop-in” systems often are only applied at a first pair of opposite sides of the floor panels, whereas then at the second pair of opposite sides, coupling parts are applied which, in the coupled condition of two floor panels, provide for a vertical as well as a horizontal locking and which allow that two of such floor panels can be coupled to each other by means of an angling movement. Floor panels with such a combination of coupling parts offer the advantage that they can be easily installed successively in rows, simply by coupling each new floor panel to be installed to the preceding row of floor panels by means of the angling movement and by providing for, when angling it down, that such floor panel simultaneously also engages in an already installed preceding floor panel of the same row. Thus, the installation of such floor panel only requires an angling and putting-down movement, which is a particularly user-friendly installation technique.
A disadvantage of floor panels with such coupling parts consists in that due to the fact that there is no locking in vertical direction, height differences between the coupled floor panels may arise at the top surface. Thus, for example, such floor panels in a first or last row of a floor covering may turn back upward from their flat position, if they are not held down by a skirting board or the like. Even if such floor panels are provided with a “drop-in” system at only one pair of sides, while being locked in horizontal as well as vertical directions at their other pair of sides in respect to adjacent floor panels, height differences may occur between adjacent floor panels at the sides coupled by the “drop-in” system, amongst others, when two adjacent floor panels are loaded differently, or when one floor panel should warp and bend somewhat in respect to the other.
Couplings of said second kind, also named “push-lock” systems, try to remedy the aforementioned disadvantage by also providing a vertical locking. Such so-called “push-lock” systems may be divided into two different categories, namely one-piece embodiments and embodiments comprising a separate locking element, which is made as an insert, whether or not fixedly attached to the actual floor panel.
One-piece embodiments are known, amongst others, from the patent documents DE 29924454, DE 20008708, DE 20112474, DE 102004001363, DE 102004055951, EP 1,282,752 and EP 1,350,904. The known one-piece embodiments have the disadvantage that they are working relatively stiff and a good joining of two floor panels can not always be guaranteed.
Embodiments comprising a separate locking element which assists in a vertical and possibly also horizontal locking between two coupled floor panels, are known, amongst others, from the patent documents DE 202007000310, DE 10200401363, DE 102005002297, EP 1,159,497, EP 1,415,056B1, EP 1,818,478, WO 2004/079130, WO 2005/054599, WO 2006/043893, WO 2006/104436, WO 2007/008139, WO 2007/079845 and SE 515324. The use of a separate locking element offers the advantage that the material thereof is independent of the actual floor panel and thus can be chosen in an optimum manner in function of the application. Thereby, such inserts may be made of synthetic material or metal, whereby relatively sturdy, however, still easily movable locking portions can be realized, which, with a minimum contact surface, can take up relatively large forces.